Throwing stones at the EU, the European project writ large and the euro is deeply unfashionable. It's a given that many Britons do think much is wrong with the EU, but saying so aloud is fraught with difficulty.

Dissenting voices are often written off as paranoid Little Englanders, closet members of the Tories or, worse, the British National Party. To question the European project's gathering speed or direction is, in the eyes of many, heresy.

EU critics are either dismissed as xenophobes overly hung up on the past, as troglodytes ludicrously attached to the Queen's head on pound notes, or worse still, as fools labouring under the misconception that Britain is best.

They are deemed, in short, to be fearful time-warped reactionaries who can't and won't recognise that the EU is the future - "they don't know what's good for them" goes the refrain - and if they're not 100 % with us then they must be 100 % against us.

But former Labour cabinet member and veteran socialist Tony Benn, a fervent anti-nationalist, succeeds where many fail, and he did so in Brussels last week with great aplomb.

Taking his highly rated one-man show Free at Last to the self-styled capital of Europe, he laid bare his views on the EU with impressive force. And in doing so he reminded many that Euroscepticism is not a dirty word (although he intensely dislikes the label on the grounds that it has become pejorative) and that there are genuine leftwing gripes with the EU which are legitimate and deserve to be aired.

In the UK his show is normally attended by the converted, but here in Brussels the audience was very different. Many of the 500 or so spectators had come along out of curiosity. Eurocrats, MEPs, lobbyists, consultants, journalists, thinktank-ers, research assistants and lawyers all crammed in to hear the 77-year old reminisce about the past and fulminate about the future.

Of course they expected a lively discourse - and they were not disappointed - but what they heard about the EU was, in many cases, not what they wanted to hear.

One of Benn's main criticisms was that there is not enough democracy in Brussels, a point with which it is hard to argue.

The European commission, he reminded the audience, is not elected and therefore not accountable, and the European parliament, he told crestfallen MEPs, is not a parliament in the real sense of the word.

Its occupants are anonymous, since people vote only for parties and not representatives (European elections use proportional representation), and the assembly's powers to legislate are limited. (It has joint competence on only a selected number of policy areas).

The real parliament and the real power is the EU's council of ministers, he added, where many decisions are taken in secret and where ministers agree laws unencumbered by national parliamentary scrutiny - despite the fact that those same laws will have a profound and irreversible effect on the people of Britain. And that, he suggested, is not democracy or anything coming close to it.

The most important question to ask someone in power, he quipped, was how you go about getting rid of them, and in the case of the European commission the disturbing answer is you can't.

It was true, he conceded, that the European parliament can trigger the collapse of the commission, but what good, he argued, was such a blunt instrument. If there is a problem with the plumbing it is nonsensical to tear down the whole house.

Spontaneous outbursts of applause punctured some of his discourse, but many of the audience whose livelihoods revolve around the EU, and who believe in it warts and all, shifted uncomfortably in their seats.

His words contrasted sharply with those uttered on an almost weekly basis by the organisers of the official debate about Europe. That debate - called the convention on the future of europe and chaired by another elder statesman, former French president Valéry Giscard d'Estaing - is leaden and impenetrable.

But Benn, puffing on his pipe and inclining his hearing aid towards his questioners, cut to the issues which really matter and did so in a genuinely engaging way.

The EU should, he claimed, evolve at the pace of national parliaments. A passionate internationalist, he would like to see a commonwealth of European states encompassing countries like Russia too.

However, in its current form the EU is, he believes, too big and too flawed to be truly democratic. There is simply no room for real debate, street politics or a meaningful link between the elected and the electors. And with the union poised to take in 10 new countries as early as 2004, he argues, things can only get worse from a democratic point of view.

A prominent Tory MEP who insisted on shouting "Hear Hear!" after any of Benn's pronouncements he liked (and there were many of them) reminded the audience that doubts about the EU and its direction are shared by the right too.

However, if Benn did anything last week it was to remind people that the Tories and the right do not and should not have a monopoly on so-called Euroscepticism, and that it is not a dirty word.